Gabe's supposed best friend and a creator of apps for a security company, who becomes entangled in ethical dilemmas. He is a key figure in the tension between security and privacy.

Jack's husband and a hacker-turned-security-expert known for his ethical approach to technology. His career and marriage to Jack provide a central focus for the narrative's unfolding events.

Jack's sister and a pragmatic journalist who supports Jack through challenging times. Her insights into criminal investigations help shape Jack's understanding of her circumstances.

A police officer and Jack's controlling ex-boyfriend, with whom she shares a troubled past. His presence complicates Jack's interactions with law enforcement.

The committed detective in charge of investigating a significant case within the story. Throughout the narrative, she scrutinizes Jack's actions and intentions.